PROJECT SUMMARY/ABSTRACT The purpose of our project is to understand the feasibility and value of collecting social media data from a cohort of teens with a chronic rheumatic condition, to augment understanding of psychosocial risks associated with chronic illness and complement structured patient-reported and clinical metrics. Detailed and sensitive investigations with longitudinally engaged cohorts of youth are needed to understand the multifaceted experience of chronic illness and the impact of the disease course and treatment on the developing child. Recognizing this, the NIH has invested in the Patient Reported Outcomes Measurement Information System (PROMIS) Pediatric item banks, which cover a myriad of physical, mental and social domains. Availability of these measures is anticipated to drive better understanding of the experience of chronic illness for affected youth in service of patient-centered care and optimal outcomes. To attain this, we need nimble and scalable approaches for engaging youth in regularly sharing information germane to their health. Social media may address this need: youth participation in social media is ubiquitous and large percentages of youth engage around health and social behaviors. Harnessing this engagement to foster research participation and sharing of patient reported outcomes (PROs) might lessen research burden, lower barriers to research participation, foster reporting about conditions/treatments, and support regular follow-up. Potential models include: 1) eliciting PROs via social media, or 2) permissioned monitoring and mining of shared social media data. Our specific aims are: Aim 1 ? Quantify willingness to share social media data for research. The main hypothesis to be tested is that compared to youth who decline, youth who share social media data will have better psychosocial functioning, fewer symptoms and lower disease activity. Aim 2 ? Understand the utility of using social media to source collection of patient-reported health information. The main hypotheses to be tested are that: (a) fluctuations in social media use will correspond to changes in health status; and (b) the content of social media posts will correspond to patients? experiences of their condition, symptoms and treatment. For each aim, we will compare social media data with clinical and PRO data acquired in the clinic. Findings will inform the nationally prioritized research goal of enabling cohort engagement and data donation for health research, and development of patient-centered interventions vital to improve outcomes.